CVE-2023-53990 SMB3: Add missing locks to protect deferred close file list
A race condition in the Linux kernel SMB3 implementation can lead to a denial of service due to missing locks on the deferred close file list.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53990?
CVE-2023-53990 is a high-severity vulnerability in Linux, published on 24 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
SMB3: Add missing locks to protect deferred close file list
cifs_del_deferred_close function has a critical section which modifies the deferred close file list. We must acquire deferred_lock before calling cifs_del_deferred_close function.
Which versions are affected by CVE-2023-53990?
How do I fix CVE-2023-53990?
Apply the vendor's patch.
Is CVE-2023-53990 being exploited?
There is no known exploitation of CVE-2023-53990 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-53990, DEBIAN-CVE-2023-53990, GHSA-8hvc-93qx-9q29, UBUNTU-CVE-2023-53990.